Identifiable Intangible Assets from Acquisitions - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Finite Lived Intangible Assets [Line Items]
Pre-tax non-cash impairment totaling	$ 4,959
Amortization of intangible assets from acquisitions	5,331	$ 6,263
Estimated amortization expense in 2021	4,900
Estimated amortization expense in 2022	1,900
Estimated amortization expense in 2023	1,800
Estimated amortization expense in 2024	602,000,000
Customer Relationships
Finite Lived Intangible Assets [Line Items]
Pre-tax non-cash impairment totaling	$ 3,430
Weighted average useful life	5 years
Technologies
Finite Lived Intangible Assets [Line Items]
Pre-tax non-cash impairment totaling	$ 1,062
Weighted average useful life	4 years
Tradenames
Finite Lived Intangible Assets [Line Items]
Pre-tax non-cash impairment totaling	$ 121
Weighted average useful life	2 years
Non-compete Agreements
Finite Lived Intangible Assets [Line Items]
Pre-tax non-cash impairment totaling	$ 346
Non-compete Agreements \| Minimum
Finite Lived Intangible Assets [Line Items]
Weighted average useful life	1 year
Non-compete Agreements \| Maximum
Finite Lived Intangible Assets [Line Items]
Weighted average useful life	3 years

Finite lived lntangible assets impairment.

No definition available.

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- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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-Topic 350
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-Section 50
-Paragraph 1
-Subparagraph (a)(3)
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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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